Differences in disease burden between neuromyelitis optica spectrum disorder and multiple sclerosis in South China.

Background: Neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) differ substantially in pathophysiological mechanisms, clinical manifestations and therapeutic management. Objectives: To investigate the disease burden of NMOSD and MS in South China and analyse the differences in disease burden between the two. Methods: We extracted the demographic characteristics, diagnoses, duration of hospitalization and mortality from the direct reporting system of health information. Results: From 2016 to 2022, the study identified 12,799 hospital admissions for 8204 patients with NMOSD and 6783 hospital admissions for 5125 patients with MS. The female-to-male ratio among patients with MS was 1.82. The peak age of NMOSD diagnosis was 45-55 years. The peak age of MS diagnosis was 25-35 years. The average duration of hospitalization for patients with NMOSD was 12 (7-17) days, whereas that for patients with MS was 10 (6-14) days. The percentage of NMOSD admissions to the intensive care unit was higher than that of MS admissions. The mortality rate for both NMOSD and MS was 0.2%. Conclusions: In South China, the disease burden of NMOSD is heavier than that of MS. The NMOSD exhibited a higher number of cases, longer duration of hospitalization and more severe clinical conditions than MS.